USGS topographic maps currently use the NAD83 coordinate system and all the layer files for the quad boundaries I can find do too. I'm wondering if there exists a nationwide GIS layer for the boundaries of the old NAD27 coordinate system that align with the neatlines for topographic maps pre-1983.
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Can you tell us why are you seeking for NAD27 for those USGS Topographic maps ? The NAD27 are really old and useless because the measurements are offset.. The newer NAD83 are much more accuary and nearly everyone use it. – PROBERT Dec 29 '17 at 16:47
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The topoView website provides GeoTiffs of historical topos that are georeferenced in NAD27 so they align with features on the ground. I would like to be able to clip the neatlines of these images but the only quad boundary layers I can find are in NAD83 so they don't align with the neatlines of these images. Re-projecting either the image or the quad boundary layer doesn't seem to make them align correctly. – cevondanady Dec 29 '17 at 17:43
